The Advancement in Detecting Sepsis and Its Outcome: Usefulness of Procalcitonin in Diagnosing Sepsis and Predicting Fatal Outcomes in Patients Admitted to Intensive Care Unit

Sepsis still remains a big challenge in patients admitted to intensive care units (ICUs) despite stellar advances made in the field of medicine. We can achieve better clinical outcomes in patients by diagnosing sepsis earlier. Procalcitonin (PCT), an inflammatory biomarker, has shown promising results in this regard. Therefore, this systematic review was done to assess the use of PCT in diagnosing and predicting severe outcomes in patients admitted to ICU and to assess if introducing PCT as a routine biochemical tool in hospitals would be helpful to achieve better clinical course in ICU patients. To identify relevant articles, we searched PubMed, Google Scholar, and references of included articles. Eligible studies were identified by two investigators independently and data were extracted. Original articles that evaluated the diagnostic and prognostic value of serum PCT levels in predicting sepsis, the severity of sepsis, and mortality among adult patients admitted to ICU were included in this study. A total of 2,063 citations were identified by the search, among which 10 studies (five prospective cohort, three retrospective cohort, one cross-sectional, and one case-control study) met the inclusion criteria. Most studies showed moderate-to-low risk of bias which was evaluated using the Quality in Prognosis Studies tool. All studies showed a positive correlation between initial PCT levels and detecting mortality resulting from sepsis, six studies found PCT helpful in detecting sepsis, and four studies evaluated the role of PCT in detecting severity in patients with sepsis. One study found area under the curve of serum PCT level for predicting 28-day mortality to be 0.82 (95% confidence interval [CI]: 0.70-0.94; p < 0.001) in adults and 0.83 (95% CI: 0.73-0.92; p < 0.001) in the elderly having an optimal cut-off level of serum PCT of 0.2 ng/mL in both the adult and elderly groups, with a sensitivity of 81 and 75% and specificity of 81.7 and 80.4%, respectively. PCT has shown promising results in detecting sepsis and its clinical course. For early diagnosis and management of sepsis, severe sepsis, and mortality in patients admitted to the ICU for a more favorable clinical outcome, PCT can be used.